Bone fastening device



Nov. 29, 1949 w. DZUS 2,489,870

BONE FASTENING DEVICE Filed March 2, 1946 INVENTOR William Dzus PatentedNov. 29, 1949 QF F ICE 1 This invention relates 'to an improvedfastening device.

It is an object of the invention to provide a i fastening device of' thequick-operating typewhich is'suitable for: usewvherethe-thickness ofzthematerials to be fastened cannot loe=accurately de- -termined-ahead-oftime,:arid in whickr thesurface of the material: is irregular andunevenand has contours therein.

fiig. 9 is a plan' view of a modified type of clip; Fig. 10 is :a side.yiew of a ;.typical installation of the first form of fastener assemblyshowingit a-pplied to:the.ankle bonesto correct ,a spread -mortise.

Referringato: .thezfirst form. of. my invention,.;the;;fasteningdevice-comprises generally a ,stud ll and a. clip ,I 2, which:are. interengageable, by .110-

A- further object of the invention is the provi-. tation ofxone'memherr-with resneettothe,other.

:sion'of "a fastening devioe of the quick acting type which is ofnon-resilient construction-so that parts fastened thereby are rigidlyandfixedly secured together.

'A'further object is the provision of arrimproved fastening device ofthe'above character which is particularly :suitable for =use -in bonesurgery 1 i or retaining fractured'bones; dislocatedjoints, spreadmortises, or the'like,in=-proper position. 'In this it" is easy toinstall that itreadily accommodates "itself to the uneven surface ofthe' boneand-can-be -easily adjusted to thevarying thicknesses: there-.of; and that it- 'eXtends-compIeteI y through -the' 1 threadedengagement "with: the bone.

"Among other objects is theprovision of animproved fastener of the abovecharacter which is relatively inexpensive to: manufacture; i simpletoinstall and operate; and which 'is rugged and sturdy in construction.

In the accompanying "drawings: Fig. 1 is-a side view of a'fastener-zassembly embodying my invention;

*Fig. 2 is a-plan view-:of -theclip-portion of the =Eig.-7 is apartially fragmentary side viewhof a modified type of stud portionEmadeofathree .parts;

Fig.1 8 is a -pantially tragmentaryyiew ofiaifurrther modified studportion;

connection, my fastener has theadvantage that 20110Qking$arii bone, andtherefore, :does not depend upon 1.25

The stud; in: the-first storm of my invention 'forrnediof two: parts.'The head: part 13 is;,f ormed iwith.a.pmtruding:threadedshank M at oneend andarheadalSzatrthecopposite end. Th head k5 Hf, preferably:provided with-some type ,of op- .eratingcmeanswherehmthestud may beated- :In the-.illustratedembo ime t, Lnwvi a ck ttrp 'coizhead havinga: hex socke as ind a a ;:l6;in;.Fig.=;4. -:The;;stud alsoprovided with;a which is gtubular in I construction and; internally br aded. soas tob n r n a ableiwithitheathread dishank l4. .A the outer end of thelocking part, I providesuitable lock- Ling orqiastenin means -.which areinterengageithtthercliD-iippnttheirotation thereof. In thellustrated-embodiment the fastening means takes the form ofthesoonventional type-0f spiral .samiastemnezm anssconsis in o a pair ofppositely -disposed spiral cam lots l8 provided 30 with .;,s hou1de r;sat ;the. inner :end thereof which l-serve ias. 1QQking-..detents.

wfl'he clip 1 I12 :15 preferably of generally elliptical shape andthe,,inner -1surface thereof is prefer- .ablyitransverseiyzeoncave, andthe outer surface ,.transverselyconvex. Ad acent the centerthereof,thecl-ipis provided(with an aperture l9 havinga cross bargzfliextendingracross one diameter thereof. 'lhescross -barn-is.of such a size as:t0 betell geablewithvthe=.spira1;slots l8 of the lockeAO v nemart: of thestudgso-that. when the stud .isro- .tated in arclockw-ise direction,thcro b w ll :floe drawninwarcilyiley-rthe spiral :slotsuntil it is dockedbehind the shoulders. 1 Rotation ofthe stud ,ina counterrqlqckwiseidirection serves to release 1171 cross .bardrom engagement with theslots. so

;as toretain thenclip firmly: in position and to lock it againstrotation-:1 preferably provide it with iinwardlvturnedgpointedm ss .2!0n the opp .--s te-.e d,s the e 1 J isiil sin my im rov d fa tening.device. the

engageable with the locking part II.

stud is first assembled by engaging the head part I3 with the lockingpart IT. The two parts are adjusted to the approximate required length.In this connection, the stud should preferably be adjusted so'that it isslightly longer than the required length. The clip is then placed on oneside of the parts to be fastened and the stud is inserted through theparts from the opposite side. The stud is then rotated to cause thespiral slots to interengage with the cross bar on the clip. Thereafter,the operator continues to rotate the head part of the stud in aclockwise direction until the length of the stud is adjusted to thethickness of the parts being fastened.

In this connection, I wish to point out that the threads on the two studparts should be so arranged that when the stud head is rotated in alocking direction, the threads are caused to interengage and tighten,and when the head is rotated in an unlocking direction, the threads arecaused to loosen. threads of the head and locking parts of the studshould fit suificiently tightly so that normally rotation of the headpart causes rotation of the locking part. However, when the locking partis ing on the tibia with the two prongs engaging the bone and the studportion II is adjusted so as to be slightly longer than the combinedthicknesses of the two bones and it is inserted thru the aperture. It isthen rotated to interlock the spiral slots with the cross bar in theclip, and

thereafter, the head is further rotated so as to firmly clamp the twobones together. It will be noted from Fig. 10 how the clip l2 readilyaccommodates itself to the angle of the external surface of the tibia.

When the fastener has been inserted and used in this fashion, it greatlyshortens the period of immobilization of the patient, and it eliminatesthe necessity of using a cast.

For internal use the fastener should, of course, be made of a materialwhich is neutral and unaffected by body-fluids, such as American Ironand Steel Institute type 316 stainless steel, and the fastener may beleft permanently in position. Under certain circumstances, of course,

the surgeon may desire at a later date to remove the fastener and this,of course, may be done.

Fastener studs of different lengths may be required and for thispurpose, head parts of different lengths may be provided. Thus, as shownin Fig. 6, I may provide a head part l3 of greatly reduced length, butwhich is otherwise similar inconstruction to the head part I3 and isinter- Thus, it has a threaded shank l4 and a head 15. The head [5 inthe form of device shown in Fig. 6, has a tapered under surface whichhas certain advantages where the head is to be applied to a surfacehaving irregular contours.

In Fig. 7, I have shown a modified type of stud il" composed of threeparts. Thus, it has a locking part I! similar to that provided in the- 4first form of my invention, a tubular internally threaded head part 24,and an intermediate connecting part 25 having threaded shanks projectingfrom the opposite ends thereof and engageable with the head andoperating parts. By rotating the head part 24 in a clockwise direction,relative to the operating part, the threads are tightened therebyshortening the length of the stud, while rotation in the oppositedirection loosens the threads and increases the length of the stud.

In Fig. 8, I have shown a further modified type of stud indicated asII'. In this form of my stud, I provide a tubular internally threadedhead part26 and a locking part 27 having a threaded projecting shank'engageable with the head part upon the rotation of head part in aclockwise direction. The locking part has spiral cam locking slotssimilar to that shown in the first form of my invention. Also, theinterengaging The exact arrangement of the cross bar 20 in the clip l2may be varied considerably. Thus, in Fig. 9, I have shown a clip l2similar in construction to the first form of the clip with the exceptionthat the cross bar 20' extends longitudinally rather than transversely.

While I have illustrated my invention as being used for the correctionof a spread ankle mortise, it will be appreciated that it has many otheruses and applications. Thus, it may be used for correcting bonefractures, dislocations, and the like, I

and may be used for many non-surgical purposes where it is desired torigidly fasten two parts together.

Modifications may, of course, be made in the illustrated and describedembodiments of my invention.

I claim:

1. In a fastening device a clip comprising a generally oval shape platewhich is transversely concave on the inner surface thereof, said clipbeing provided with inwardly projectin prongs on the opposite endsthereof, and with a centrally positioned aperture having locking meansassociated therewith.

2. A fastening device for use in orthopedic surgery comprising a clipconsisting of a plate having an aperture therein with locking meansassociated therewith, and a stud having locking means adjacent one endwhich is interengageable with the locking means of the clip when the endof the stud is inserted in the aperture, the diameter of the aperturebeing greater than the diameter of said end of the stud to permit tiltinof the clip with respect to the stud.

3. A fastening device for use in orthopedic surgery comprising a clipconsisting of a plate having an aperture therein with locking meansassociated therewith, a stud having a head part and a locking parthaving threaded connecting means, the locking part having locking meansadjacent one end thereof which is interengageable with the locking meansof the clip when the end of the locking part is inserted in the apertureand rotated in one direction, the threaded connecting means beingarranged so that it is tightened when the head part is rotated in adirection to cause the locking means to interengage with the clip andthe diameter of the aperture in the clip being greater than the diameterof the looking part so as to permit tilting of the clip with respect tothe stud.

4. A fastening device for use in orthopedic surgery comprisin a clipconsistin of a plate having an aperture therein with locking means gagewith the clip.

WILLIAM DZUS.

REFERENCES CITED The following references are of record in the file ofthis patent:

5 UNITED STATES PATENTS Number Name Date 945,737 Anderson Jan. 11, 19101,841,575 Dorsch Jan. 19, 1932 10 2,389,184 Cooke Nov. 20, 1945

